Proteomics screen to reveal molecular changes mediated by C722G missense mutation in CHRM2 gene
Dongyan Hou1, Ying Chen, Jiamei Liu
1Heart Failure Center, Department of Cardiology, Capital Medical University, Chao-Yang Hospital, Beijing, China.
Unlabelled:
Previously, we reported a missense mutation (C722G) in the M2-muscarinic acetylcholine receptor (CHRM2) gene associated with familial dilated cardiomyopathy. However, the exact molecular mechanisms by the related protein changes of CHRM2-C722G mutation induced are still unclear. CHRM2 and CHRM2-C722G lentiviral vector was infected to CHO cells. Proteomic analysis by label-free shotgun strategy and the STRING 9.0 software were performed. A total of 102 proteins with at least 2-fold change in the CHRM2-C722G group were identified, 42 proteins were up-regulated, whereas 57 were down-regulated. These altered proteins belong to three broad functional categories: (i) metabolic (e.g. Cytosolic acyl coenzyme A thioester hydrolase, Malate dehydrogenase); (ii) cytoskeletal (e.g. Actin-related protein, Myosin light polypeptide 6 and Alpha-actinin-1) and (iii) stress response (e.g. heat shock protein 70, Ras-related protein Rab-10). Interestingly, the marked differences in the expression of selected eight proteins (change >4.0-fold), were connected with many proteins related to apoptosis and immune/inflammatory response such as: FOS, BAX, MYC, TP53 and IL6. This novel study demonstrated for the first time a full-scale screening of the proteomics research by CHRM2-C722G mutation and profiled 102 changed proteins, of which, eight might be critical in cardiac dysfunction for future mapping.
Significance:
It was a full-scale screening of the proteomics research by CHRM2-C722G mutation. These proteins might serve as valuable biomarkers that could predict the presence of a precursor field. These proteins might serve to further explore the pathophysiological mechanisms in familial DCM patients with C176W mutation.
Insights
A mutation in the muscarinic acetylcholine receptor 2 (CHRM2) gene is linked to familial dilated cardiomyopathy. This study identified 102 altered proteins, including eight key proteins potentially involved in cardiac dysfunction.
Area of Science:
- Cardiovascular Genetics
- Molecular Biology
- Proteomics
Background:
- Familial dilated cardiomyopathy (DCM) has been linked to mutations in the M2-muscarinic acetylcholine receptor (CHRM2) gene, specifically C722G.
- The precise molecular mechanisms underlying the protein alterations caused by the CHRM2-C722G mutation remain largely unknown.
Purpose of the Study:
- To investigate the molecular mechanisms of the CHRM2-C722G mutation in familial DCM.
- To perform a comprehensive proteomic analysis to identify proteins affected by the CHRM2-C722G mutation.
Main Methods:
- Lentiviral vectors expressing CHRM2 and CHRM2-C722G were used to infect Chinese Hamster Ovary (CHO) cells.
- Label-free shotgun proteomic analysis was employed to identify differentially expressed proteins.
- STRING 9.0 software was utilized for protein-protein interaction network analysis.
Main Results:
- A total of 102 proteins showed at least a 2-fold change in expression in cells with the CHRM2-C722G mutation compared to wild-type CHRM2.
- 42 proteins were upregulated, and 57 were downregulated, categorized into metabolic, cytoskeletal, and stress response pathways.
- Eight proteins exhibited significant expression changes (>4.0-fold) and were linked to apoptosis and immune/inflammatory responses, including FOS, BAX, MYC, TP53, and IL6.
Conclusions:
- This study presents the first large-scale proteomic screening of the CHRM2-C722G mutation, identifying 102 altered proteins.
- Eight identified proteins may be critical in the pathogenesis of cardiac dysfunction in familial DCM.
- These proteins could serve as potential biomarkers for predicting disease presence and for further elucidating pathophysiological mechanisms in familial DCM patients.
